Re: [PATCH] of/irq: Don't ignore interrupt-controller when interrupt-map failed

From: Marc Zyngier
Date: Fri Nov 12 2021 - 10:28:51 EST


On Fri, 12 Nov 2021 15:04:15 +0000,
Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
>
> On Fri, Nov 12, 2021 at 02:36:44PM +0000, Marc Zyngier wrote:
> > Since 041284181226 ("of/irq: Allow matching of an interrupt-map local
> > to an interrupt controller"), the irq code favors using an interrupt-map
> > over a interrupt-controller property if both are available, while the
> > earlier behaviour was to ignore the interrupt-map altogether.
> >
> > However, we now end-up with the opposite behaviour, which is to
> > ignore the interrupt-controller property even if the interrupt-map
> > fails to match its input. This new behaviour breaks the AmigaOne
> > X1000 machine, which ships with an extremely "creative" (read:
> > broken) device tree.
> >
> > Fix this by allowing the interrupt-controller property to be selected
> > when interrupt-map fails to match anything.
> >
> > Fixes: 041284181226 ("of/irq: Allow matching of an interrupt-map local to an interrupt controller")
> > Reported-by: Christian Zigotzky <chzigotzky@xxxxxxxxxxx>
> > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
> > Link: https://lore.kernel.org/r/78308692-02e6-9544-4035-3171a8e1e6d4@xxxxxxxxxxx
> > Cc: Rob Herring <robh@xxxxxxxxxx>
> > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>
> I'm not qualified to review this, but since 041284181226 was merged
> via my tree along with the rest of the Apple stuff, let me know if
> you'd like me to merge this.
>
> I see Rob has a comment, so if you want to take care merging it
> yourself, that's certainly fine with me.

I have a couple of IRQ patches that need to go in, so happy to route
it via the irqchip tree if Rob gives his blessing.

M.

--
Without deviation from the norm, progress is not possible.